#!/usr/bin/env python3
# -*- coding=utf-8 -*-
# 题目：将一个正整数分解质因数。例如：输入90,打印出90=2*3*3*5。


def f1(n):
    m = n
    k = int(n**0.5) + 1
    bds = ""
    x = 2
    while x <= k:
        if m % x == 0:
            m /= x
            bds += f"{x}*"
            continue
        else:
            x += 1

    if bds == "":
        print(f"{n} : 1*{n}")
    else:
        bds = bds[:-1]
        print(f"{n} : {bds}")


f = f1
if __name__ == "__main__":
    f(9)
    f(12)
    f(29)
    f(45)
